New species of ‘exploding ant’ discovered in Borneo

Researchers have revealed a new species of exploding ant, which they discovered living in the rainforest canopy of Brunei on the island of Borneo.

Named Colobopsis explodens, the new ant ruptures its abdomen when threatened, killing itself in the process. This rupturing releases a sticky, yellow, toxic goo that has a spicy smell.

The researchers expect more exploding ant species will be described in the near future.

High up in the treetops of Borneo live “exploding ants,” so named because of their unique defensive behavior. When a potential enemy threatens their colony, these ants kill themselves by rupturing their own abdomens to release a sticky, repellant liquid.

Now, researchers have identified a new species of exploding ant in Brunei, fittingly named Colobopsis explodens. Previously lumped in with the species Camponotus saundersi, the new species sports a number of differences, including a yellower defensive liquid that led the researchers to nickname the species “Yellow Goo.” Their description was published today in ZooKeys.

“They explode when attacked by an enemy (or poked with a finger),” lead author Alice Laciny with the University of Vienna, told CBC News. “The composition of the goo is currently under investigation, but it certainly contains sticky and toxic components.”

In their study, the researchers noted that C. explodens is especially trigger-happy when it comes to its unusual defense in that it is “particularly prone to self-sacrifice when threatened by enemy arthropods, as well as intruding researchers.” They describe its ooze as bright yellow with “a distinctive spice-like” smell.

Because of these attributes, as well as its abundance and the fact that the scientists were able to observe their suicidal behavior both in the wild and in controlled lab settings, the researchers have chosen C. explodens to be the “model species” for the exploding ant group. This means that it will serve as a focal point for future exploding ant research.

According to the study, only “minor worker” ants engage in suicidal explosion. But other colony members have their own unique behaviors, such as the “doorkeepers” that use their enlarged, blunt heads to plug up nest openings.

While individually tiny, rainforest ants like the newly described C. explodens, are hugely influential to their surrounding ecosystems. Previous research indicates ants may make up around 86 percent of the arthropod biomass (i.e., the mass of insects, spiders, etc.) in tropical forests, and may play a big role in their carbon cycling.

The researchers expect more exploding ant species will be described in the near future.